package com.emo.wowoblog.utils;

import java.util.ArrayList;
import java.util.List;


//负责传入一个大的集合，根据页号返回所需要的数据
/*
 * 页数=
 记录条数%每页条数＝＝0     记录条数/每页条数
 否则          记录条数/每页条数+1
 第N页显示第几条记录(记录从0开始算)? (N-1)*每页条数=<序号< N*每页条数
 * */
public class Pager<T> {
	private List<T> bigList; // 大的集合，外界传入
	private int curentPageIndex = 1; // 当前页号，外界传入
	private int countPerpage = 2; // 每页条数，外界可以设定
	private List<T> smallList; // 小的集合，返回
	private int pageCount; // 页数
	private int recordCount; // 记录条数
	private int prePageIndex; // 上一页序号
	private int nextPageIndex; // 下一页序号
	private boolean firstPage; // 是否第一页
	private boolean lastPage; // 是否最后一页

	public void setCurentPageIndex(int curentPageIndex) { // 每当页数改变，都会调用这个函数，筛选代码可以写在这里
		this.curentPageIndex = curentPageIndex;

		// 上一页，下一页确定
		prePageIndex = curentPageIndex - 1;
		nextPageIndex = curentPageIndex + 1;
		// 是否第一页，最后一页
		if (curentPageIndex == 1) {
			firstPage = true;
		} else {
			firstPage = false;
		}
		if (curentPageIndex == pageCount) {
			lastPage = true;
		} else {
			lastPage = false;
		}
		// 筛选工作
		smallList = new ArrayList<T>();
		for (int i = (curentPageIndex - 1) * countPerpage; i < curentPageIndex
				* countPerpage
				&& i < recordCount; i++) {
			smallList.add(bigList.get(i));
		}
	}

	public int getCurrentPageIndex() {
		return curentPageIndex;
	}

	public List<T> getBigList() {
		return bigList;
	}

	public void setBigList(List<T> bigList) {
		this.bigList = bigList;
		// 计算条数
		recordCount = bigList.size();
		// 计算页数
		if (recordCount % countPerpage == 0) {
			pageCount = recordCount / countPerpage;
		} else {
			pageCount = recordCount / countPerpage + 1;
		}

		// 筛选工作
		smallList = new ArrayList<T>();
		for (int i = (curentPageIndex - 1) * countPerpage; i < curentPageIndex
				* countPerpage
				&& i < recordCount; i++) {
			smallList.add(bigList.get(i));
		}

	}

	public int getCountPerpage() {
		return countPerpage;
	}

	public void setCountPerpage(int countPerpage) {
		this.countPerpage = countPerpage;
	}

	public List<T> getSmallList() {
		return smallList;
	}

	public void setSmallList(ArrayList<T> smallList) {
		this.smallList = smallList;
	}

	public int getPageCount() {
		return pageCount;
	}

	public void setPageCount(int pageCount) {
		this.pageCount = pageCount;
	}

	public int getRecordCount() {
		return recordCount;
	}

	public void setRecordCount(int recordCount) {
		this.recordCount = recordCount;
	}

	public int getNextPageIndex() {
		return nextPageIndex;
	}

	public void setNextPageIndex(int nextPageIndex) {
		this.nextPageIndex = nextPageIndex;
	}

	public int getPrePageIndex() {
		return prePageIndex;
	}

	public void setPrePageIndex(int prePageIndex) {
		this.prePageIndex = prePageIndex;
	}

	public boolean isFirstPage() {
		return firstPage;
	}

	public void setFirstPage(boolean firstPage) {
		this.firstPage = firstPage;
	}

	public boolean isLastPage() {
		return lastPage;
	}

	public void setLastPage(boolean lastPage) {
		this.lastPage = lastPage;
	}

}
